We just moved into a new home and discovered that one of the rooms had a door with a big window on it, and three other large windows, which was letting in all the cold air from outside. It was also letting out the heat that was being generated in the room and we were all freezing at night- even though we had curtains on all the windows! We discovered Shutters we could put on the windows that would help with blocking the cold/hot air from coming in/escaping and we were able to get comfortable in the new room. It’s amazing what can help you!